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Electronics Repair (sci.electronics.repair) Discussion of repairing electronic equipment. Topics include requests for assistance, where to obtain servicing information and parts, techniques for diagnosis and repair, and annecdotes about success, failures and problems. |
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#1
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Very old GE TV dies- what could be wrong?
I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box,
cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'.] |
#2
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Very old GE TV dies- what could be wrong?
On Jul 18, 10:58*pm, Stan wrote:
I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'.] I suspect that it could be the power supply not the picture tube but I can be wrong. |
#3
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Very old GE TV dies- what could be wrong?
On Sat, 19 Jul 2008 05:58:35 +0000, Stan wrote:
The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. Just to be absolutely certain... if you disconnect the TV from the digital box, does it still go dead after a few minutes? (I'm betting it does, but you'd hate to throw the TV away only to find the problem was the digital box...) |
#4
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Very old GE TV dies- what could be wrong?
Stan wrote:
I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'.] One can't be certain, but I'll hazard a guess -- Assuming it's a color set, it'll have a protective circuit that shuts it down (in order to avoid X-ray emissions) if the picture tube begins to draw too much current. Either that circuit is failing/has drifted out of tolerance, or something else causes the current draw to enter the "danger" zone once the set warms up. -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form . |
#5
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Very old GE TV dies- what could be wrong?
In article , CJT wrote: The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. One can't be certain, but I'll hazard a guess -- Assuming it's a color set, it'll have a protective circuit that shuts it down (in order to avoid X-ray emissions) if the picture tube begins to draw too much current. Either that circuit is failing/has drifted out of tolerance, or something else causes the current draw to enter the "danger" zone once the set warms up. There might also be a cracked solder joint on the board, which is opening and closing as a result of thermal cycling when the set warms up. A bad joint in the right place could shut down portions of the set's power supply. -- Dave Platt AE6EO Friends of Jade Warrior home page: http://www.radagast.org/jade-warrior I do _not_ wish to receive unsolicited commercial email, and I will boycott any company which has the gall to send me such ads! |
#6
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Very old GE TV dies- what could be wrong?
On Sat, 19 Jul 2008 13:26:54 -0400, Meat Plow wrote:
....... My next step would be to observe just how it shuts down. Does it appear as if someone just hit the off button? Yes, the failure is exactly like someone hitting the OFF button. Does it display any anomalies either sound or picture-wise or does it again just look like it was turned off? No anomalies-- it just goes off. However, just recently and only while this problem has been going on, I've noticed that while the TV is briefly working, a station *might* suddenly turn to static- just static sound and no picture. I switch to another channel and all is OK with that one and with the others. [We only get 6 free, broadcast TV channels in my city.] Does the TV get its AC source from the converter? No, and I've disconnected the TV from the Magnavox HD converter box. The power comes thru the cord plugged into the wall outlet (via an extension cord). Other things connected to this same outlet are fine: a box fan and a clock. If it just shuts off like you turned it off I would first suspect the power supply then measure some voltages therein to see what happens as/when it shuts down. Thanks Meat Plow for your help. Since I never deal with or mess with electronics, I might be able to find someone who knows how to do these tests. [To contact me, drop one ' i '.] |
#7
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Very old GE TV dies- what could be wrong?
"stan74" wrote in message ... On Sat, 19 Jul 2008 13:26:54 -0400, Meat Plow wrote: ....... My next step would be to observe just how it shuts down. Does it appear as if someone just hit the off button? Yes, the failure is exactly like someone hitting the OFF button. Does it display any anomalies either sound or picture-wise or does it again just look like it was turned off? No anomalies-- it just goes off. However, just recently and only while this problem has been going on, I've noticed that while the TV is briefly working, a station *might* suddenly turn to static- just static sound and no picture. I switch to another channel and all is OK with that one and with the others. [We only get 6 free, broadcast TV channels in my city.] Does the TV get its AC source from the converter? No, and I've disconnected the TV from the Magnavox HD converter box. The power comes thru the cord plugged into the wall outlet (via an extension cord). Other things connected to this same outlet are fine: a box fan and a clock. If it just shuts off like you turned it off I would first suspect the power supply then measure some voltages therein to see what happens as/when it shuts down. Thanks Meat Plow for your help. Since I never deal with or mess with electronics, I might be able to find someone who knows how to do these tests. [To contact me, drop one ' i '.] I wouldn't trust anything Meat Plow has to say. Just go to http://groups.google.com/group/24hoursupport.helpdesk and search Meat Plow and his alter ego "Kadaitcha Man" and come to your own conclusion. |
#8
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Very old GE TV dies- what could be wrong?
Hi,
apart form the other suggestions - don't forget to test the electrolytic caps in the power supply. A dry electro could be the cause too. Greg "Stan" wrote in message ... I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'.] |
#9
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Very old GE TV dies- what could be wrong?
On Jul 20, 1:07*pm, Meat Plow wrote:
On Sat, 19 Jul 2008 19:14:40 +0000, stan74 wrote: On Sat, 19 Jul 2008 13:26:54 -0400, Meat Plow wrote: ....... My next step would be to observe just how it shuts down. Does it appear as if someone just hit the off button? Yes, the failure is exactly like someone hitting the OFF button. Does it display any anomalies either sound or picture-wise or does it again just look like it was turned off? No anomalies-- it just goes off. However, just recently and only while this problem has been going on, I've noticed that while the TV is briefly working, a station *might* suddenly turn to static- just static sound and no picture. I switch to another channel and all is OK with that one and with the others. [We only get 6 free, broadcast TV channels in my city.] Does the TV get its AC source from the converter? No, and I've disconnected the TV from the Magnavox HD converter box. The power comes thru the cord plugged into the wall outlet (via an extension cord). Other things connected to this same outlet are fine: a box fan and a clock. If it just shuts off like you turned it off I would first suspect the power supply then measure some voltages therein to see what happens as/when it shuts down. Thanks Meat Plow for your help. Since I never deal with or mess with electronics, I might be able to find someone who knows how to do these tests. To the seasoned vet those sets are pretty straight forward. I used to do GE warranty among others back in the 80s. I wouldn't sink much money in it however.- Hide quoted text - - Show quoted text - The first thing to do is try another tv set in place of your set. if it also fails after a few minutes, then it is the convertor box that is dying. The freezing of the picture is typical of a convertor problem. Magnavox is made by Funai which is the cheapest convertor and has gotten a very bad reputation due to the high failure rate of their convertors. Bob Hofmann |
#10
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Very old GE TV dies- what could be wrong?
On Sat, 19 Jul 2008 05:58:35 +0000, Stan wrote:
I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'. This television came with a service manual attached in a box on the back. If you could scan and upload the schematic to media fire or a binary group, it might jog my memory. I worked for a high volume GE repair center when that set was new and have probably seen most common failures. Chuck |
#11
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Very old GE TV dies- what could be wrong?
Chuck wrote:
On Sat, 19 Jul 2008 05:58:35 +0000, Stan wrote: I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'. This television came with a service manual attached in a box on the back. If you could scan and upload the schematic to media fire or a binary group, it might jog my memory. I worked for a high volume GE repair center when that set was new and have probably seen most common failures. Chuck And your reply jogged my memory a bit. Didn't a lot of those GEs have problems with solder joints on large lugged connections? ISTR a couple of those I worked on back in the 80's (for friends; I was never a commercial tech) which would just 'die'. The fix was to rework all of the solder joints where large 'stuff' was attached to the main PCB. It seems they didn't get them hot enough, and the larger components (especially chokes and transformers) sinked away so much heat that the joints were not viable. In fact, I recall one on which I had to resort to my 100/150 watt Weller gun to get enough heat going.... jak |
#12
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Very old GE TV dies- what could be wrong?
On Mon, 21 Jul 2008 18:00:50 -0400, Meat Plow
wrote: On Mon, 21 Jul 2008 14:41:35 -0500, jakdedert wrote: Chuck wrote: On Sat, 19 Jul 2008 05:58:35 +0000, Stan wrote: I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'. This television came with a service manual attached in a box on the back. If you could scan and upload the schematic to media fire or a binary group, it might jog my memory. I worked for a high volume GE repair center when that set was new and have probably seen most common failures. Chuck And your reply jogged my memory a bit. Didn't a lot of those GEs have problems with solder joints on large lugged connections? ISTR a couple of those I worked on back in the 80's (for friends; I was never a commercial tech) which would just 'die'. The fix was to rework all of the solder joints where large 'stuff' was attached to the main PCB. It seems they didn't get them hot enough, and the larger components (especially chokes and transformers) sinked away so much heat that the joints were not viable. In fact, I recall one on which I had to resort to my 100/150 watt Weller gun to get enough heat going.... I recall feed through points on GE TV boards of that era having sub standard soldering. Your right, but that issue was resolved by the time the PP chassis came out except for the tuner assembly. Chuck |
#13
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Very old GE TV dies- what could be wrong?
On Mon, 21 Jul 2008 14:41:35 -0500, jakdedert
wrote: Chuck wrote: On Sat, 19 Jul 2008 05:58:35 +0000, Stan wrote: I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'. This television came with a service manual attached in a box on the back. If you could scan and upload the schematic to media fire or a binary group, it might jog my memory. I worked for a high volume GE repair center when that set was new and have probably seen most common failures. Chuck And your reply jogged my memory a bit. Didn't a lot of those GEs have problems with solder joints on large lugged connections? ISTR a couple of those I worked on back in the 80's (for friends; I was never a commercial tech) which would just 'die'. The fix was to rework all of the solder joints where large 'stuff' was attached to the main PCB. It seems they didn't get them hot enough, and the larger components (especially chokes and transformers) sinked away so much heat that the joints were not viable. In fact, I recall one on which I had to resort to my 100/150 watt Weller gun to get enough heat going.... jak There was something that would break loose in the switched power supply or the horizontal section and the width pot would burn up and the set would go dead. It was a very common problem but without the schematic, I can't remember what it was. Chuck |
#14
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Very old GE TV dies- what could be wrong?
On Mon, 21 Jul 2008 13:01:38 -0500, Chuck wrote:
This television came with a service manual attached in a box on the back. Yes Chuck, that's right. There's a cut out window in the plastic box on the back of the TV. Thru the window one easily sees the instructions with words that say the instructions/manual/schematics are only available if the TV box is opened up, something I've not yet done due to what I write below. If you could scan and upload the schematic to media fire or a binary group, it might jog my memory. I worked for a high volume GE repair center when that set was new and have probably seen most common failures. Chuck When I turned on the TV two days ago, it was totally dead: it wouldn't even start up. So it seems the symptoms I told you about when I started this thread were early signs of eventual TV death which is now the case. Is it still worthwhile to see the schematics? I'd have to open up the TV box and then look somewhere in town for a scanner. [I don't own one.] |
#15
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Very old GE TV dies- what could be wrong?
I had a fancy '85 RCA with the exact same problem, and the cause took some
time narrow down. Turns out the horizontal output transistor was shorting after it warmed up, causing the switching power supply to shut down (without blowing fuses etc - wish they still built stuff this well). Replacing the transistor fixed the set. If you aren't familiar with the inner workings of a TV, I'd recommend taking it to a professional. A competent and honest tech should be able to fix it for a reasonable price. The most bizarre cause of this problem I ever saw was on an old Electrohome from the early 80's. Believe it or not, the primary winding on the flyback was opening after the flyback warmed up - I never saw anything like that before or since. "CJT" wrote in message ... Stan wrote: I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'.] One can't be certain, but I'll hazard a guess -- Assuming it's a color set, it'll have a protective circuit that shuts it down (in order to avoid X-ray emissions) if the picture tube begins to draw too much current. Either that circuit is failing/has drifted out of tolerance, or something else causes the current draw to enter the "danger" zone once the set warms up. -- The e-mail address in our reply-to line is reversed in an attempt to minimize spam. Our true address is of the form . |
#16
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Very old GE TV dies- what could be wrong?
"Meat Plow" wrote in message ... On Tue, 22 Jul 2008 09:52:12 -0500, Chuck wrote: On Mon, 21 Jul 2008 18:00:50 -0400, Meat Plow wrote: On Mon, 21 Jul 2008 14:41:35 -0500, jakdedert wrote: Chuck wrote: On Sat, 19 Jul 2008 05:58:35 +0000, Stan wrote: I've enjoyed for 8 years a nice, jumbo sized, handsome real wood box, cubic shaped, on-a-lazy-susan-base, GE TV, model 25PP5859K (built in Nov. 1984). I bought it used in 2000. I don't have or want cable TV-- I only watch free, broadcast type TV shows. [I've had this TV connected for maybe the past 1.5 months to a cheap Magnavox TV converter box.] The other day I turned on the TV, it worked fine for a few minutes and then suddenly goes dead. This pattern can be repeated after a short rest of the TV: it goes on, picture looks fine and sound is OK and then suddenly dies -- goes totally silent and black -- after a few minutes running. What could be wrong with it? Does this sound like it's the main picture tube which is shot or something else? [This TV must have been a costly, state-of-the-art one when it came out in 1984, so I guess the best electronics for its time were used in its construction.] Tell me what you think or suspect. Thanks [To contact me, drop one 'i'. This television came with a service manual attached in a box on the back. If you could scan and upload the schematic to media fire or a binary group, it might jog my memory. I worked for a high volume GE repair center when that set was new and have probably seen most common failures. Chuck And your reply jogged my memory a bit. Didn't a lot of those GEs have problems with solder joints on large lugged connections? ISTR a couple of those I worked on back in the 80's (for friends; I was never a commercial tech) which would just 'die'. The fix was to rework all of the solder joints where large 'stuff' was attached to the main PCB. It seems they didn't get them hot enough, and the larger components (especially chokes and transformers) sinked away so much heat that the joints were not viable. In fact, I recall one on which I had to resort to my 100/150 watt Weller gun to get enough heat going.... I recall feed through points on GE TV boards of that era having sub standard soldering. Your right, but that issue was resolved by the time the PP chassis came out except for the tuner assembly. Chuck Ah ok, it's been awhile. I just recall repairing literally hundreds of those things especially the 19" sets. Got pretty good at it and could knock out a dozen of those a day with few if any reruns. They were actually a good set with VIR and good color. Owned a couple of them bought used from people who left them at the shop for whatever reasons. If I recall correctly, one of them belonged to Kadaitcha Man and he wouldn't take it back after you two fags broke up. |
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